A scientist whose observations of drowned polar bears raised alarms about climate change has received $100,000 to settle a whistle-blower complaint against an agency of the Department of the Interior.

Under the settlement, wildlife researcher Charles Monnett retired from his job at the federal Bureau of Ocean Energy Management on Nov. 15, and the agency agreed to remove a letter of reprimand that officials had placed in his file.

"Well, it's over, in the sense that my relationship with the department and the federal government is over," says Monnett. "I am still a scientist. I still have some standing in the scientific community. I may continue to play a role in some fashion, particularly in the Arctic. That's yet to be seen."

NPR requested comment from the Bureau of Ocean Energy Management but a spokeswoman said the agency could not comment on personnel matters.

"Sound science is the foundation of BOEM's decision-making, and therefore we take the integrity of our scientists and the reliability of their work very seriously," said spokeswoman Connie Gillette in an email. "We are proud of the exceptional scientists at BOEM and of BOEM's scientific programs."

The settlement document states that it does not constitute any admission of liability and that the agency entered into it to avoid the costs of litigation.

The settlement ends a controversial saga that began back in 2004, when Monnett saw drowned polar bears while flying over the Arctic during a routine aerial survey of whales. He reported on the dead bears in a scientific journal, and Al Gore mentioned them in the movie An Inconvenient Truth. The dead polar bears became a potent symbol of the threat of melting ice.

But in 2010, the Department of the Interior's Office of Inspector General received allegations of scientific misconduct from a federal employee. Investigators repeatedly interrogated Monnett and a colleague about their report of dead polar bears.

Monnett believes this was an effort to silence scientific efforts that might interfere with oil and gas development in the Arctic. He says his wife and son were harassed — "by people who didn't like my politics, whatever they perceived them to be."

Last year, the investigation ended. And Monnett's employer, the Bureau of Ocean Energy Management, said it did not look like he had engaged in any scientific misconduct. But the agency did officially reprimand Monnett for an unrelated matter, leaking internal government documents.

"I thought that was silly," Monnett says. "It seemed desperate, on the part of the agency. They stick this letter in my file and end it, and tell me to just forget about everything and let's just move on. ... It just seemed like a desperate attempt to justify a hole that the department had dug itself into."

So Monnett lodged a whistle-blower complaint, with the help of Public Employees for Environmental Responsibility, saying that the five emails he had sent to outside individuals showed that the agency was breaking laws to push through Arctic offshore drilling permits.

In addition to the other agreements in the settlement, the agency promised to issue a certificate for a conservation award from the secretary of the interior. (The group representing Monnett says that he won it in 2010 but that the agency removed his name.)

And Monnett agreed to not reapply to any position with the Department of the Interior for five years.

"Well, I'm sad, I guess. It's been disappointing," says Monnett. "As a young person, fresh out of graduate school, I was idealistic, and I thought that it would all be about the truth."